Wiring for a trailer?

STumped

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Hi all,

I already have a hitch installed and plan to tow a small trailer with LED lights. I see on the FJR1300 forum that there is a plug-n-play wiring harness for a trailer from Admore that is very popular:

https://www.admorelighting.com/product/a-fjr2/?search=fjr

They don't make one for the ST1300 so my question is, is there anything like this for a ST1300? If not, what do you recommend to isolate the trailer wiring?

Thanks in advance. :)
 

Blrfl

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That's probably possible on the FJR if there's a subharness for that part of the bike. On the ST, the lines for the rear lights come directly out of the main harness.

--Mark
 

rjs987

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There used to be a sticky thread in this forum on just that subject with solutions for an isolated trailer connection. Found it, it was moved to articles HERE. I have electrical diagrams if you are interested for a DIY one which is what I used on my Gold Wing and ST1100. Electrical Connection has a universal kit HERE but it is a little pricey. Mine is also what I consider a universal since I've used it on many other bikes besides my own (different makes/models) and is not specific to any. My current version of it is in the photo from my Flickr albums. You would just need to pay attention to the upper part of the diagram unless you also want to add a LED light bar with brake and running tail light to the rear of the bike (which I did on my CTX1300). This diagram is what I was intending to use for my current bike and the same as for my past bikes. But then I decided not to put the trailer part on and not pull a trailer... yet. I can still add that part later with what I already have installed (I did add the LED bar). The wires used to tap into for left, right, and brake relays may likely be different color codes for the ST1300 than for my CTX if Honda is not consistent there.



You can click on the photo for a larger view and also to go to my Flickr album to see other diagrams. In my gallery in this forum (panel on the left) I have photos showing detail of how I wired this on my ST.

Oh, I only show a 5 wire trailer plan since the bike is native to providing a 5 wire setup. Most made for motorcycle trailers do have a 5 wire setup as well... or should. The 4 wire systems that still hang around in the USA are OLD old school that were common due to American cages only coming with 4 wire setups. All vehicles overseas (both east and west of the USA) are 5 wire internally so makes sense to stay that way. That only means the turn lights are separate from the brake lights for a 5 wire setup. More lights in back = better. :)
 
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ScubaDave

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I have used a universal 5 to 4 trailer converter on 3 ST1300's with no issues. All wires can be found in the tail section on the RH side.
 
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STumped

STumped

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Ok, so it turns out that the trailer has a five wire connection so that is good. It also has LED lights so I am wondering if it would be safe to just tap into the existing wires for a power source since the LED draw such little current? If that's not such a great idea, what if I replace the existing lights on the bike to LED's to lower their current draw?
 

T_C

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I'm sure some will warn of fire and brimstone, but this is what I do. My bike and trailer are LED, my trailer was wired by myself so I know the wiring is good and won't be randomly shorting out. KISS theory works for me (but I did re-wire the trailer so it has a 5 and 4 wire connector for use behind the car, but I'm geeky that way).

PS I did have a 5-4 adapter on the bike (used it for my third brake light/turn signal thingie) but found out it did not like having LED's on the bike side of the convertor. So it went away and everyone has been living in happy harmony since then.
 
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rjs987

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I have a Toyota Corolla with a plug-n-play trailer connection... or used to anyway. It's been replaced now with another newer one but just haven't installed the trailer setup. There were 2 ways I was considering to make the new connections for a trailer. Since both my old ST (which is the bike I had wired for a trailer) and the Corolla (being a non-USA designed cage) are natively 5 wire systems I was considering option 1 as simply to leave off the 5 to 4 converter that was in the plug-n-play harness for the cage and connect the trailer wires directly as a 5 wire system. Option 2 was to enable the trailer to be used as either a 4 wire or 5 wire system by using one of 2 pigtails between the trailer plug and the vehicle plug. I would wire the trailer with a left and right brake, a separate left and right turn signal lamps, and the running and ground wire. The turn signal lamps would have red lenses instead of amber. All 6 wires would go to a 6 pin plug on the trailer. One pigtail would covert that 6 pin to a 5 pin tying together the brake light wires but leaving the turn lights separate from the brakes. The other pigtail would convert the 6 pin to a 4 pin by tying together the brake and turn on each side to work together (left brake and turn tied, right brake and turn tied). These pigtails would be simple and there would be no electrical gizmo or device with any programmed circuit to fail. Instead I replaced my ST and sold the trailer and I haven't considered getting another trailer... yet.

It would be something like this:



Just threw this together while taking a short break at work but this is what has been on my mind about this.
 
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ScubaDave

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Ok, so it turns out that the trailer has a five wire connection so that is good. It also has LED lights so I am wondering if it would be safe to just tap into the existing wires for a power source since the LED draw such little current? If that's not such a great idea, what if I replace the existing lights on the bike to LED's to lower their current draw?
The only issue I can see would be a short. If you want to be safe add an inline fuse to the wires with a low amp fuse in them.
 
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